Which is the correct sentence?

[Tan Elaine]

1. The plant's reactor Nos 1, 2 and 3 shut down automatically when the quake hit.
2. The plant's reactors Nos 1, 2 and 3 shut down automatically when the quake hit.

Which sentence should I use?

Many thanks.

[SoothingDave]

If 1, 2 and 3 are 3 different reactors, as I suspect, then sentence 2 is correct.

[Tan Elaine]

Thanks, SoothingDave.

Am I right to say that the same applies to the following sentence?

Cashier orders Nos. 234, 235 and 236 are missing.

[SoothingDave]

Yes.